Demonstration of improved heteroepitaxy, scaled gate stack and reduced interface states enabling heterojunction tunnel FETs with high drive current and high on-off ratio

Staggered tunnel junction (GaAs
_0.35
Sb
_0.65
/In
_0.7
Ga
_0.3
As) is used to demonstrate heterojunction tunnel FET (TFET) with the highest drive current, I
_on
, of 135μA/μm and highest I
_on
/I
_off
ratio of 2.7×10
⁴
(V
_ds
=0.5V, V
_on
-V
_off
=1.5V). Effective oxide thickness (EOT) scaling (using Al
₂
O
₃
/HfO
₂
bilayer gate stack) coupled with pulsed I-V measurements (suppressing D
_it
response) enable demonstration of steeper switching TFET.